The Central Ground Water Board (CGWB) released its “Annual Groundwater Quality Report – 2024,” which highlights alarming levels of contamination in the groundwater across India. The findings focus on nitrate, fluoride, arsenic, uranium, and electrical conductivity, revealing potential health risks and environmental concerns.
Nitrate Contamination
- Extent of Nitrate Contamination: The report indicates that 20% of groundwater samples exceed the permissible nitrate concentration of 45 mg/l, as set by the World Health Organisation (WHO) and the Bureau of Indian Standards (BIS).
- Geographical Impact: States like Rajasthan, Karnataka, and Tamil Nadu show over 40% of samples exceeding the nitrate limit. Other states such as Maharashtra (35.74%), Telangana (27.48%), Andhra Pradesh (23.5%), and Madhya Pradesh (22.58%) also report significant contamination.
- High-Risk Areas: Fifteen districts have been identified as the most affected, including Barmer and Jodhpur in Rajasthan, Wardha and Buldhana in Maharashtra, and Villupuram in Tamil Nadu.
Fluoride Contamination
- Exceeding Safe Limits: The report reveals that 9.04% of groundwater samples contain fluoride levels above the safe limit.
- Concerned States: Rajasthan, Haryana, Karnataka, Andhra Pradesh, and Telangana are most affected by high fluoride concentrations.
Arsenic Contamination
- Arsenic Levels: 3.55% of the samples show arsenic contamination exceeding the permissible limit of 10 parts per billion (ppb).
- Affected Regions: The Ganga and Brahmaputra floodplains, especially in West Bengal, Jharkhand, Bihar, Uttar Pradesh, Assam, Manipur, and parts of Punjab and Chhattisgarh, are at risk.
Uranium Contamination
- Uranium Levels: 42% of samples from Rajasthan and 30% from Punjab show uranium concentrations above 100 ppb.
- Health Risks: Chronic exposure to uranium can lead to kidney damage. The report indicates that uranium contamination is particularly prevalent in over-exploited and critical groundwater stress zones.
Electrical Conductivity
- High Conductivity: States like Rajasthan, Delhi, Gujarat, Haryana, Punjab, Telangana, Andhra Pradesh, and Karnataka have high electrical conductivity values in groundwater, indicating poor water quality.
Causes of Groundwater Contamination
- Agricultural Practices: Excessive use of nitrogen-based fertilizers and poor management of animal waste contribute significantly to nitrate contamination.
- Urbanization: Population growth leads to increased wastewater and sewage, which often contains high nitrate levels.
- Water Over-exploitation: Over-exploited groundwater zones, such as those in Rajasthan, Punjab, and Haryana, show a higher risk of uranium contamination.
Multiple-Choice Questions (MCQs):
- What percentage of groundwater samples in India exceeded the permissible nitrate concentration?
- A) 10%
- B) 15%
- C) 20%
- D) 25%
- Which state reported the highest percentage of nitrate contamination in groundwater?
- A) Rajasthan
- B) Maharashtra
- C) Karnataka
- D) Tamil Nadu
- Which of the following states has high fluoride concentrations exceeding the permissible limit?
- A) Kerala
- B) Rajasthan
- C) Punjab
- D) Uttar Pradesh
- Which health issue is associated with high nitrate levels in groundwater?
- A) Skin lesions
- B) Blue baby syndrome
- C) Kidney damage
- D) Cancer
- Which of the following states is most affected by uranium contamination in groundwater?
- A) Punjab
- B) Maharashtra
- C) Gujarat
- D) Rajasthan
- What is the primary cause of high nitrate levels in groundwater?
- A) Urbanization
- B) Excessive irrigation and fertilizer use
- C) Industrial waste
- D) Poor sewage disposal
- Which regions are identified as hotspots for uranium contamination?
- A) Coastal areas
- B) Over-exploited groundwater zones
- C) Floodplains of the Ganga and Brahmaputra
- D) Urban centers
- What is the potential health risk of long-term exposure to arsenic in groundwater?
- A) Fluorosis
- B) Skin lesions and cancer
- C) Blue baby syndrome
- D) Kidney damage